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1.
The structures of the oxygenated fatty acids of the lipids ofOnopordum acanthium L. seeds have been studied by the methods of chemical, chromatographic, and spectral analyses. Triepoxy acids of the C18 series and 24 monohydroxy acids with chain lengths of C14–C18 have been identified, of which the 8-OH-9Z,12Z-18:2 and the 14-OH-9Z,12Z-18:2 acids have been isolated as natural compounds for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 515–518, July–August, 1993.  相似文献   

2.
The structures of fatty monohydroxy acids of the lipids of the seeds ofGaleopsis bifida Boenn. have been studied by the methods of chromatographic, spectral, and chemical analysis. (31) Acids with chain lengths of from 14 to 20 carbon atoms, with from 0 to 3 double bonds, and with the hydrolyls in positions characteristic for the products of the direct hydroxylation and the lipoxygenase and photosensitized oxidation of unsaturated fatty acids were detected. Of them, the 13-OH-9Z, 11E-17:2, the 15-OH-9, 12-18:2, the 16-OH-9, 12-18:2, and 17-OH-11, 14-20:2 acids were new, while this is the first time that the 15-OH-9Z, 12Z, 16E-18:3 acid has been described as a natural compound. The behavior of the TMS derivatives of the hydroxy acids on a polyester phase in GLC is discussed.  相似文献   

3.
The structures of fatty monohydroxy acids of the lipids of the seeds ofGaleopsis bifida Boenn. have been studied by the methods of chromatographic, spectral, and chemical analysis. (31) Acids with chain lengths of from 14 to 20 carbon atoms, with from 0 to 3 double bonds, and with the hydrolyls in positions characteristic for the products of the direct hydroxylation and the lipoxygenase and photosensitized oxidation of unsaturated fatty acids were detected. Of them, the 13-OH-9Z, 11E-17:2, the 15-OH-9, 12-18:2, the 16-OH-9, 12-18:2, and 17-OH-11, 14-20:2 acids were new, while this is the first time that the 15-OH-9Z, 12Z, 16E-18:3 acid has been described as a natural compound. The behavior of the TMS derivatives of the hydroxy acids on a polyester phase in GLC is discussed.Institute of the Chemistry of Plant Substances, Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 744–753, November–December, 1991.  相似文献   

4.
The composition of the fatty mono- and dihydroxy acids of the fruit ofRumex paulsenianus Rech. fil. (familyPolygonaceae) has been determined by a combination of IRS, UVS, GLC, and mass-spectrometric methods. (22) Monohydroxy acids of the C14–C20 series, including isomers and isologues, and four dihydroxy acids from C18 to C20, including a new isomeric 9-OH-10, 12–17:2 acid have been detected.  相似文献   

5.
The composition of the fatty mono- and dihydroxy acids of the fruit ofRumex paulsenianus Rech. fil. (familyPolygonaceae) has been determined by a combination of IRS, UVS, GLC, and mass-spectrometric methods. (22) Monohydroxy acids of the C14–C20 series, including isomers and isologues, and four dihydroxy acids from C18 to C20, including a new isomeric 9-OH-10, 12–17:2 acid have been detected.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 762–765, November–December, 1991.  相似文献   

6.
Abstract

Structures of 1,8-(ArZ)2C14H6O2 and 9-(MeO)-1,8-(ArZ)2C14H7 (Z = S, Se) are determined by X-ray crystallographic analysis. Five C─Z- - -O- - -Z─C atoms of the compounds align linearly, which are analyzed by the extended hypervalent 5c–6e model, based on QC calculations. CT of the 5c–6e occurs as the σ*(C─Z) ← n p (O)→ σ*(Z─C) direction.  相似文献   

7.
Two C20-diterpene alkaloids have been isolated from the epigeal part ofAconitum coreanum (Levl.) Rapaics: the known 14-hydroxy-2-isobutyrylhetesine (I) (Guan-Fu base Z) and a new one — acorine (II), C22H29NO5, mp 214–215°C (from acetone), α D 20 +9° (c 0.01; methanol), for which the structure of 2-acetyl-14-hydroxy-hetesine has been established. Details of the IR, mass, and13C NMR spectrum of (I) and (II) and of the PMR spectrum of (II) are given.  相似文献   

8.
Z-6-Heneicosen-11-one (1) and Z-1,6-Heneicosen-11-one (2) are the sex pheromones of the Douglas-Fir Tussock moth, ‘Orgyia Pseudo Sugata’, isolated1,2 in 1975 and 1978 respectively. In contrast with other lepidopterous pheromones, which are unsaturated C12-C14 primary alcohols or acetates, these were found to be C21 ketones. The Douglas-Fir Tussock moth is a severe defoliator of the Fir forest; consequently, considerable interest attends the synthesis of these two pheromones. A number of syntheses of these two pheromones have been reported3 amongst which is one of our synthesis using N,N-dimethyl acetone 4 hydrazone as key intermediate.  相似文献   

9.
The correct identification of drying oils plays an essential role in providing an understanding of the conservation and deterioration of artistic materials in works of art. To this end, this work proposes the use of peak area ratios from fatty acids after ensuring that the linear responses of the detector are tested. A GC-MS method, previously reported in the literature, was revisited to its developed and validated in order to identify and quantify of eight fatty acids that are widely used as markers for drying oils in paintings, namely myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), suberic acid (2C8), azelaic acid, (2C9) and sebacic acid (2C10). The quaternary ammonium reagent m-(trifluoromethyl)phenyltrimethylammonium hydroxide (TMTFAH) was used for derivatization prior to GC-MS analysis of the oils. MS spectra were obtained for each methyl ester derivative of the fatty acids and the characteristic fragments were identified. The method was validated in terms of calibration functions, detection and quantification limits and reproducibility using the signal recorded in SIR mode, since two of the methyl derivatives were not totally separated in the chromatographic run. The proposed method was successfully applied to identify and characterise the most widely used drying oils (linseed oil, poppy seed oil and walnut oil) in the painting La Encarnación. This 17th century easel painting is located in the main chapel of the cathedral in Granada (Spain) and was painted by the well-known artist of the Spanish Golden Age, Alonso Cano (1601-1667).  相似文献   

10.
Lactic acid bacteria strains Lactobacillus plantarum CWBI-B534 and Leuconostoc ssp. mesenteroïdes (L. mesenteroïdes) Kenya MRog2 were produced in bioreactor, concentrated, with or without cryoprotectants. In general, viable population did not change significantly after freeze-drying (p?>?0.05). In most cases, viable population for cells added with cryoprotectants was significantly lower than those without (p?16:0), palmitoleic (C16:1), stearic (C18:0), oleic (C18:1), linoleic (C18:2), and linolenic (C18:3) acids were identified. Four of them, C16:0, C16:1, C18:0, and C18:1, make up more than 94% or 93% of the fatty acids in L. mesenteroides and L. plantarum, respectively, with another one, namely, C18:3, making a smaller (on average 5–6%, respectively) contribution. The C18:2 contributed very small percentages (on average?≤?1%) to the total in each strain. C16:0 had the highest proportion at most points relative to other fatty acids. Moisture content and water activity (a w) increased significantly during the storage period. It was observed that C16:1/C16:0, C18:0/C16:0 and C18:1/C16:0 ratios for freeze-dried L. mesenteroides or L. plantarum, with or without cryoprotectants, did not change significantly during the storage period. According to the packaging mode and storage temperatures, C18:2/C16:0 and C18:3/C16:0 ratios for freeze-dried L. mesenteroides and L. plantarum with or without cryoprotectants decreased as the storage time increased. However, a higher C18:2/C16:0 or C18:3/C16:0 ratio for L. mesenteroides and L. plantarum was noted in the freeze-dried powder held at 4 °C or under vacuum and in dark than at 20 °C or in the presence of oxygen and light.  相似文献   

11.
Summary Gas-liquid chromatographic analysis on capillary column in combination with mass spectrometry (LKB 9000) gave evidence for the occurence of positional isomers of monoenoic fatty acids in human milk. After high vacuum fractional distillation, mercury adducting and preparative gas-liquid chromatography the even numbered monoenoic fatty acid methyl esters from C10–C18 were obtained in a purity of better than 99.5%. Samples of 1 mg were oxidized by a modified reagent according to von Rudloff. Resulting mono- and dicarboxylic acids were analysed by gas-liquid chromatography. Overoxidation as determined with pure 9-octadecenoic acid was in the order of 1.5%. The number of isomers detected for C10, C12, C14, C16 and C18 enoic acids were 8, 10, 10, 12, 9, respectively.
Stellungsisomere Monoenfettsäuren in der Muttermilch
Zusammenfassung Gas-Chromatographie auf Capillarsäule in Kombination mit Massenspektrometrie (LKB 9000) gab Anhaltspunkte für das Vorliegen stellungsisomerer Monoenfettsäuren in der Muttermilch. Die geradzahligen Monoenfettsäuren von C10 bis C18 wurden durch fraktionierte Destillation im Hochvakuum, Quecksilber-Adduktbildung und präparative Gas-Chromatographie in einer Reinheit von besser als 99,5% dargestellt. Trans-Fettsäuren konnten nicht nachgewiesen werden. Die oxydative Spaltung nach v. Rudloff erfolgte an Proben von je 1 mg, wobei die erhaltenen Mono- bzw. Dicarbonsäuren als Methylester gas-chromatographisch quantitativ analysiert wurden. Die Optimierung der Spaltansätze erfolgte mittels reiner 9-Octadecensäure. Unter den angegebenen Bedingungen war eine Überoxydation von maximal 1,5% zu beobachten. Die Zahlen der gefundenen Isomeren betragen 8, 10, 10, 12 und 9 für die C10, C12, C14, C16 und C18 Monoensäuren in der angegebenen Reihenfolge.
  相似文献   

12.
The sphingolipids 1a , b and 2a , b which play important roles in epidermal barrier function, were synthesized by N-acylation of C18-sphingosine 3 and 1-O-glucosylated C18-sphingosine 6 , respectively, with ω-acyloxy-substituted fatty acids 4 and 5 (Scheme 1). These fatty acids were obtained from ω-hydroxy-substituted fatty acids 8 and 9 by esterification with linoleic acid ( 7 ). The C34-fatty acid 8 was prepared as follows: C25-Compound 18 was obtained by means of a Wittig reaction of C13-aldehyde 13 with C12-phosphonium salt 15 or of C12-aldehyde 24 with C13-phosphonium salt 21 , respectively, and subseqent hydrogenation and O-deprotection (Scheme 2). Alternatively, 8 was prepared via 30 by copper-catalyzed coupling of C13-alkyl halide 19 with the Grignard reagent derived from C12-alkyl bromide 14 (Scheme 2). Oxidation of 18 to aldehyde 39 and Wittig reaction with C9-phosphonium salt 41 furnished the desired ω-hydroxy-substituted fatty acid 8 , after O-deprotection (Scheme 3). Similarly, Wittig reaction of C11-phosphonium salt 22 with C12-aldehyde 24 furnished C23-aldehyde 40 , after hydrogenation, O-deprotection, and oxidation; Wittig reaction with compound 41 and subsequent deprotection afforded the desired C32-fatty and 9 (Scheme 3). an alternative strategy furnished compound 8 by a coupling reaction of alkyne 53 with ω-bromo-substitued fatty acid 52 , obtained from compounds 24 and 47 by Wittig reaction, hydrogenation, and introduction of bromide (Scheme 4). Hydrogenation (Lindlar's catalyst) of the resulting C34-alkyne 54 and deprotection furnished 8 .  相似文献   

13.
Extraction of the comminuted seeds has yielded an oil from which have been isolated: C33-C25, C18 and C17 paraffinic hydrocarbons, C18:1, C18:2, C18:3, C17:1, C17:2 and C17:3 olefinic hydrocarbons, ethyl esters of C32:0, C31:0, C30:0, C29:0, and C28:0 fatty acids, sterols with molecular weights of 414, 412, and 400, and the alcohols α-amyrin and lupeol with their natural acetates. Extraction of the uncomminuted seeds has shown that the paraffinic hydrocarbons, ethyl esters, and alcohol acetates pass into the oil from the husks of the seeds. This is the first time that the C31:0 and C29:0 fatty acids have been detected as natural compounds, and it is the first time that the ethyl esters of C34, C33, C32, C31, and C30 fatty acids have been isolated from seed oils of higher plants.  相似文献   

14.
The original lipid content of the thylakoid membranes of moss Marchantia polymorpha has been determined for the first time. In particular, the content of SQDG is almost 3 times higher than those for both of the other classes. The ratios for DGDG and MGDG are just a little bit lower than those for green algae, but almost 2 times less than those for plants. The distribution of unsaturated bonds has changed in C18 -residues of fatty acids. The total content of C18-residues in thylacoid lipids have been almost the same but the content of C18:1, C18:2 and C18:3 are altered in the fractions of DGDG, PG and PE. The light stress produces only the quantitative, but no qualitative, changes of the thylakoid lipid composition. The properties of the thylakoid lipids and corresponding fatty acids in the monolayers at the liquid/gas interfaces have been studied. The changes in distribution of unsaturated bonds in C18 residues of fatty acids at light stress have been confirmed by Langmuir method.  相似文献   

15.
The following compounds have been identified in the lipids of the petals ofCarthamus tinctorius: C32 and C29 isoparaffins; free fatty acids, the main component of which is palmitic acid; 33 esters of phytol, esterified with three groups of fatty acids — paraffinic, isoparaffinic, and monoenoic of the C9–C26 series; and β-sitosterol and its β-D-glucopyranoside.  相似文献   

16.
The TMS derivatives of the hydroxyacyldiacylglycerides of sea buckthorn seed oil have been analyzed by mass spectrometry. On the basis of characteristic fragments it has been established that an acyl residue of one of the seven hydroxy acids found previously in hydrolysis products by the GC-MS method is attached in one of the positions of the hydroxyacyldiacylglycerides. The remaining positions are substituted by acyl radicals of the C18:1, C18:2, C18:3 and C18:0 acids. The 24 most probable components of the triglycerides include these acyl and hydroxyacyl substituents. Features of the fragmentation of the components due to presence of polyunsaturated acids have been revealed.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 176–182, March–April, 1991.  相似文献   

17.
Thermodynamics on inclusion complexation of β-cyclodextrin (β-CD) with n-alkylpyridinium chlorides (C n PC, n = 12, 14, 16) were measured by conductivity technique to evaluate the effects of chain length of C n PC and temperature. The data obtained indicate that inclusion complexes S(CD) and S(CD)2 had formed between surfactant and β-CD in aqueous solution. Investigation showed that the K 1 (first equilibrium constant) for S(CD) formation is greater than K 2 (second equilibrium constant) for S(CD)2 formation. It has been found that C12PC forms only the 1:1 complex, while C14PC and C16PC form 1:1 and 1:2 complexes. Thermodynamic parameters of the complexation, i.e. ΔG°, ΔH° and ΔS° have been also calculated. The large values of ΔG° indicate that complexation between surfactant and β-CD is very favorable.  相似文献   

18.
Thirty triorganotin(IV) derivatives of the type R3Sn(R′COCHCOCH2COR″) and [R3Sn]2 (R′COCHCOCHCOR″) (where R = CH3, C2H5, nC3H7, nC4H9 and C6H5 and R′ = R″ = CH3, C6H5 or R′ = C6H5, R″ = CH3) have been synthesised by the interaction of R3SnCl with mono- or disodium salt of 2, 4, 6-heptanetrione, 1-phenyl-1, 3, 5-hexanetrione and 1, 5-diphenyl-1, 3, 5-pentanetrione in 1:1 and 2:1 molar ratios, respectively. The complexes have been examined by their molecular weight, IR, PMR and elemental analyses and their tentative structures assigned. Both “Z” and “E” forms have been identified in the 1:1 complexes in equilibrium with the enol form containing five coordinate tin. The 2:1 derivatives contain one five- and other four coordinated tin(IV) except the phenyl analogue where both the tins are five coordinated.  相似文献   

19.
Extraction of the comminuted seeds has yielded an oil from which have been isolated: C33-C25, C18 and C17 paraffinic hydrocarbons, C18:1, C18:2, C18:3, C17:1, C17:2 and C17:3 olefinic hydrocarbons, ethyl esters of C32:0, C31:0, C30:0, C29:0, and C28:0 fatty acids, sterols with molecular weights of 414, 412, and 400, and the alcohols -amyrin and lupeol with their natural acetates. Extraction of the uncomminuted seeds has shown that the paraffinic hydrocarbons, ethyl esters, and alcohol acetates pass into the oil from the husks of the seeds. This is the first time that the C31:0 and C29:0 fatty acids have been detected as natural compounds, and it is the first time that the ethyl esters of C34, C33, C32, C31, and C30 fatty acids have been isolated from seed oils of higher plants.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 612–615, September–October, 1979.  相似文献   

20.
《中国化学快报》2023,34(7):108065
The development of novel adjuvants constitutes a new strategy for the research of tumor vaccines. Immunomodulatory molecule adjuvants are one of the novel adjuvants that can effectively stimulate the pattern recognition receptors to activate the downstream pathways of immune cells. However, there are few studies on immunomodulatory molecular adjuvants associated with C-type lectin. It has been reported that GlcC14C18 is a Mincle ligand with a relatively simple structure and strong adjuvant activity in vivo. Herein, we coupled GlcC14C18 with MUC1 glycopeptide and evaluated its immune effect. In addition, we also synthesized α-GlcC14C18-MUC1 and β-GlcC14C18-MUC1 based on the two configurations of GlcC14C18 and compared their immune effects. The results show that both of the two configurations of the vaccine have a good immune effect, but to a certain extent, the immune effect of β-GlcC14C18-MUC1 is better than that of α-GlcC14C18-MUC1.  相似文献   

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